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Random variables can be adjusted to satisfy a specific constraint.

For example we might adjust the variable x to be always greater than the variable y by using
the command \randadjustIf{x,y}{x<=y}

The command \randadjustIf has the syntax \randadjustIf{[varlist]}{[relation]} .

• varlist comma separated list of variables to be adjusted
• relation a relation that defines an avoidance condition under which the variables
123456789101112\begin{question}     \begin{variables}        \randint[Z]{x}{-10}{10}        \randint[Z]{y}{-10}{10}        \drawFromSet{a}{1,2,3}        \drawFromSet{b}{1,2,3}        \randadjustIf{x,y}{x <= y} %adjust x and y if x is not greater than y        \randadjustIf{b}{a = b}    %adjust b if b equals a    \end{variables} \end{question} 

The avoidance_relation has to be a logical (boolean) combination (use $$NOT$$, $$AND$$, $$OR$$) of simple comparison
relations $$(=, !=, <, <=, >, >=)$$ between expressions in the variables.

These expressions may include random and non-random variables defined in the same variable
environment.

See Expressions And Relations
for a more detailed description.

Hint:

• Make sure that the avoidance relation can be avoided at all for the random variables with the ranges given.
The \randint commands jointly define a product set which has to have a non-empty intersection with the
complement of the avoidance set. Otherwise you get a runtime error when the problem is run.
• Even if the intersection is non-empty but has a equi-distribution probability being too small,
a runtime error might be the result, though the algorithm tries its best to find an admissible point.
\randadjustIf on a variable defined by \drawFromSet only works for (the default) type _number_

You may call randadjustIf multiple times to adjust disjoint lists of variables as in the following example:

1234567891011\begin{question}    \begin{variables}        \randint[Z]{x}{-10}{10}        \randint[Z]{y}{-10}{10}        \randint[Z]{c}{-10}{10}        \randint[Z]{d}{-10}{10}        \randadjustIf{x,y}{x <= y} %adjust x and y if x is not greater than y        \randadjustIf{c,d}{c = d OR c = x}    \end{variables} \end{question} 
You should *NEVER* adjust the same variable twice. The following example might lead to problems:
12345678910111213\begin{question}     \begin{variables}        \randint[Z]{x}{-10}{10}        \randint[Z]{y}{-10}{10}        \randint[Z]{c}{-10}{10}        \randint[Z]{d}{-10}{10}        \randadjustIf{x,y}{x <= y} %adjust x and y if x is not greater than y        \randadjustIf{c,x}{c = d OR c = x} % here the variable x will be re-adjusted                                            % and the constraint from previous randadjustIf might be broken.    \end{variables} \end{question} 

You may use \randadjustIf in the same